Bleach doesnt work.
Besides (with the powdered bleach in your wallet idea) you dont really want to get caught with a small baggie of white powder in your wallet, do you?
Listerine may work, but if you drink a bottle of listerine you shouldnt smoke buds because you're already too much of a retard.
The best thing to do is stay on the creep with your mom, and get yourself some aqua-clear, or another variety of piss cleaner. Then, when your mom tells you to take a test, tell her you just took a piss, and then immediately take your cleaner. wait an hour or however long you are supposed to then take your test. you should pass with no problems.